循环是Python里写得最多的结构，但大多数人写来写去就是for x in list加range(len())。那些能省掉嵌套、避免flag变量、让循环自解释的技巧，往往用到的时候才后悔没早点知道。 循环是Python里写得最多的结构，但大多数人写来写去就是for x in list加range(len())。那些能 ...

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